Karla Homolka and Paul Bernardo

Rap Sheet: The Canadian couple was convicted of raping and killing three women between 1990 and 1992, while Bernardo committed at least 13 additional sexual assaults.

Crime History: Karla Homolka and Paul Bernardo, later known as "the Ken and Barbie Killers," met in 1987 and were wed in 1991, but Bernardo came into the relationship with a disturbing and lengthy history of sexual assault. From 1987 to 1990, Bernardo raped at least 13 women between the ages of 15 and 22 in a suburb of Toronto, and committed attempted rape of at least six other women, most of whom he stalked after they got off buses during the late evening. Bernardo wouldn’t be officially pinpointed as the "Scarborough Rapist" until 1993, when DNA evidence linked him to the crimes, but he was considered a suspect in November 1990 after police received two tips that Bernardo matched the composite given by one of victims. During his interview with police, Bernardo voluntarily gave samples for forensic testing, and charmed them into concluding that "he was far more credible" than the tipsters, who "might just be trying to collect the reward." He was released the following day, and the samples were simply set aside.

Homolka was physically and psychologically abused by Bernardo, but at the same time, she encouraged his sadistic sexual behavior. In late December 1990, Homolka helped Bernardo drug, rape and ultimately kill her 15-year-old sister Tammy in her parents’ basement; Karla later explained she wanted to give him the teen’s virginity as a Christmas present. Tammy choked on her own vomit while she was unconscious and later died at a local hospital, but the couple was able to convince family and the authorities that the teen’s death was accidental. A few weeks later, they filmed a notorious video called "The Fireside Chat," in which Homolka dressed up as Tammy, and she and Bernardo discuss their enjoyment of the crime before having sex on Tammy’s bed. They went on to abduct, rape and murder three more teenage girls, videotaping the torture of one and encasing another's dismembered body in cement.

In February 1993, investigators in Toronto finally analyzed the blood Bernardo had given back in 1990, and found that Bernardo’s DNA matched the DNA of semen samples they had gathered from three of the rape victims. In February 1993, after being interrogated by the police, Homolka confessed and implicated her husband in the murders as well.

Homolka agreed to a 12-year plea bargain in exchange for cooperation, accusing Bernardo of as many as 30 other sexual assaults. Bernardo was ultimately sentenced to life in prison with the possibility of parole, though in 1995 he was declared a "Dangerous Offender," making it unlikely that he will ever be released. Karla Homolka, meanwhile, was released from prison in July 2005, and since has remarried and had three children.